*{
  margin: 0;
  padding: 0;
}
/* 1vw 就是视口宽度的 1%   1vh 就是视口高度的 1% */
.container{
  width: 100vw;
  height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  background: radial-gradient(rgb(187, 200, 204), rgb(59, 68, 189));
}

.slider-wrapper {
  width: 480px;
  height: 270px;
  position: relative;
}

.btn{
  width: 50px;
  height: 50px;
  background: white;
  position: absolute;
  top: 110px;
  font-size: 20px;
  font-weight: bold;
  text-align: center;
  line-height: 50px;
  border-radius: 50%;
  opacity: 0.7;
  user-select: none;
  cursor:pointer;
}

.next{
  right: 0;
}